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Kamisetty NK Pack SP Nonogawa M Devarayapalli KC Kodaki T Makino K 《Analytical and bioanalytical chemistry》2006,386(6):1649-1655
Aminosilane-treated molecular layers on glass surfaces are frequently used as functional platforms for biosensor preparation.
All the amino groups present on the surface are not available in reactive forms, because surface amino groups interact with
remaining unreacted surface silanol groups. Such nonspecific interactions might reduce the efficiency of chemical immobilization
of biomolecules such as DNA, enzymes, antibodies, etc., in biosensor fabrication. To improve immobilization efficiency we
have used additional surface silanization with alkylsilane (capping) to convert the remaining silanol groups into Si–O–Si
linkages, thereby liberating the amino groups from nonspecific interaction with the silanol groups. We prepared different
types of capped amine surface and evaluated the effect of capping on immobilization efficiency by investigating the fluorescence
intensity of Cy3-NHS (N-hydroxysuccinimide) dye that reacted with amino groups. The results indicate that most of the capped amine surfaces resulted
in enhanced efficiency of immobilization of Cy3-NHS compared with the untreated control amine surface. We found a trend that
trialkoxysilanes had greater capping effects on immobilization efficiency than monoalkoxysilanes. It was also found that the
aliphatic chain of alkylsilane, which does not participate in the capping of the silanol, had an important function in enhancing
immobilization efficiency. These results would be useful for preparation of an amine-modified surface platform, with enhanced
immobilization efficiency, which is essential for developing many kinds of biosensors on a silica matrix.
Enhancement of amine funtionality by capping with alkylsilane 相似文献
2.
Kamisetty NK Pack SP Nonogawa M Devarayapalli KC Watanabe S Kodaki T Makino K 《Analytical and bioanalytical chemistry》2007,387(6):2027-2035
Amine-modified oligodeoxynucleotides (AMO) are commonly used probe oligodeoxynucleotides for DNA microarray preparation. Two
methods are currently used for AMO preparation—use of amine phosphoramidites protected by acid-labile monomethoxytrityl (MMT)
groups or alkali-labile trifluoroacetyl (TFA) groups. Because conventional AMO preparation procedures have defects, for example
stringent acidic conditions are required for deprotection of MMT and hydrophobic purification cannot be used for TFA-protected
amino groups, conventional preparation of AMO is unlikely to result in the expected outcome. In this paper a method of AMO
synthesis using modified H-phosphonate chemistry is suggested. An aliphatic diamine is coupled with a phosphonate group forming
a phosphoramidate linkage to the last internucleotide phosphate of oligodeoxynucleotides. In this method dimethoxytrityl (DMT)
purification steps are used and stringent acid deprotection is not required to obtain the AMO. Although the method could lead
to formation of AMO diastereomers, melting-temperature and CD analysis showed for two AMO that DNA duplex formation was the
same as when normal oligodeoxynucleotides were used. Also, when these AMO were used as probes for DNA microarrays the immobilization
efficiency was similar to that for AMO probes prepared by conventional means using an amino-modifier unit. The hybridization
performance of these AMO was better than for those prepared conventionally. The procedures suggested would be useful for preparation
of efficient AMO for fabrication of DNA microarrays and DNA-based nanoparticle systems.
Nagendra Kumar Kamisetty and Seung Pil Pack have equally contributed to this work. 相似文献
3.
K.C. Devarayapalli S.V. Prabhakar Vattikuti T.V.M. Sreekanth Ki Soo Yoo P.C. Nagajyothi Jaesool Shim 《应用有机金属化学》2020,34(3):e5376
Herein, cobalt (Co)-based metal–organic zeolitic imidazole frameworks (ZIF-67) coupled with g-C3N4 nanosheets synthesized via a simple microwave irradiation method. SEM, TEM and HR-TEM results showed that ZIF-67 were uniformly dispersed on g-C3N4 surfaces and had a rhombic dodecahedron shape. The photocatalytic properties of g-C3N4/ZIF-67 nanocomposite were evaluated by photocatalytic dye degradation of crystal violet (CV), 4-chlorophenol (4-CP) and photocatalytic hydrogen (H2) production. In presence of visible light illumination, the photocatalytic dye results showed that 95% CV degradation and 53% 4-CP degradation within 80 min. The H2 production of the g-C3N4/ZIF-67 composite was 2084 μmol g−1, which is 3.84 folds greater than that of bare g-C3N4 (541 μmol g−1). 相似文献
4.
Rao KS Rani SU Charyulu DK Kumar KN Lee BK Lee HY Kawai T 《Analytica chimica acta》2006,576(2):177-183
A novel approach for immobilization of probe oligonucleotides that uses zirconium phosphate modified silica nanoparticles is proposed. The surface modification of nanoparticles was carried out in two stages. Initially binding of Zr4+ to the surface of silica nanoparticles and later treated with phosphoric acid for terminal phosphate groups. Oligonucleotide probes modified with amine group at 5'-end were strongly binds to the phosphate terminated silica nanoparticles with imidazole in presence of 0.1 mol L(-1) EDC [N-ethyl-N'-(3-dimethylaminopropyl) carbodiimide], as phosphate groups are more reactive towards amine group. Various studies, i.e., synthesis of silica nanoparticles, their surface modification, probe immobilization, measurement of hybridization and effect of bovine serum albumin (BSA) were carried out during optimization of reaction conditions. The significant reduction in the background signal was observed by treating the probe modified silica nanoparticles with bovine serum albumin prior to hybridization. The probe modified silica nanoparticles were retained their properties and the hybridization was induced by exposure of single-stranded DNA (ssDNA) containing silica nanoparticles to the complementary DNA in solution. The decrease in the fluorescence signal for one mismatch and three mismatch was observed upon hybridization of probe with target DNAs, while there was no response for the random target ssDNA under the same experimental conditions. The intensity of fluorescence signal was linear to the concentration of target DNA ranging from 3.9 x 10(-9) to 3.0 x 10(-6)mol L(-1). A detection limit of 1.22 x 10(-9) mol L(-1) of oligonucleotides can be estimated. The proposed hybridization assay is simple and possesses good analytical characteristics and it can provide an effective and efficient route in the development of DNA biosensors and biochips. 相似文献
5.
Ramaraghavulu Rajavaram Rao V. Koteswara Devarayapalli K. C. Yoo Kisoo Nagajyothi P. C. Shim Jaesool 《Research on Chemical Intermediates》2021,47(2):637-648
Research on Chemical Intermediates - The green synthesis of nanoparticles using plant-based materials as an alternative to chemical and physical routes provides economic and environmental benefits.... 相似文献
6.
Pack SP Heo TH Devarayapalli KC Makino K 《Analytical and bioanalytical chemistry》2011,401(2):667-676
Although a DNA-immobilized packed-column (DNA-packed column), which relies on sequence-dependent interactions of target DNA
or mRNA (in the mobile phase) with DNA probes (on the silica particle) in a continuous flow process, could be considered as
an alternative platform for quantitative analysis of specific DNA to DNA chip methodology, the performance in practice has
not been satisfactory. In this study, we set up a more efficient quantitative analysis system based on a DNA-packed column
by employing a temperature-gradient strategy and DMSO-containing mobile phase. Using a temperature-gradient strategy based
on T
m values of probe/target DNA hybridizations and DMSO (5%)-containing mobile phase, we succeeded in the quantitative analysis
of a specific complementary target distinguishable from non-complementary DNA oligomers or other similar DNA samples. In addition,
two different target DNA oligomers even with similar T
m values were separated and detected quantitatively by using a packed column carrying two different DNA probes. 相似文献
7.
Devarayapalli KC Pack SP Kamisetty NK Nonogawa M Watanabe S Kodaki T Makino K 《Analytical and bioanalytical chemistry》2007,388(4):919-928
DNA chips prepared on a flat glass surface have unavoidable drawbacks when used for quantitative analysis. In an attempt to
overcome this problem, we constructed an HPLC-type system suitable for quantitative analysis that enables base sequence- and
T
m-dependent DNA oligomer separation in a flow system. A small open tubular capillary column (300-mm × 100-μm I.D.) was used.
The DNA oligomers used as probes had an amino group at the 5′-end and were immobilized on the inner silica surface of the
capillary column which had been sequentially treated with 3-aminopropyltriethoxysilane, butyltrimethoxysilane, and disuccinimidylglutarate.
Using the combination of probe-immobilized column placed in a column oven equipped with temperature gradient function, a nano-flow-controllable
pump, a small sample-loading injector, and a capillary-fitted UV detector, we succeeded in separating complementary and non-complementary
DNA oligomers in specific and quantitative modes. We also designed a temperature gradient strategy for efficient separation
of target DNA oligomers in DNA mixture samples. Using a column carrying two different probes with similar T
m values, their complementary target DNA oligomers were also separated and detected. The developed DNA open tubular capillary
column system investigated in the present study could be further improved as an alternative tool to DNA chips to be used for
the quantitative analysis of DNA or mRNA samples.
Kamakshaiah Charyulu Devarayapalli and Seung Pil Pack contributed equally to this paper. 相似文献
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